Experienced founder & back-end dev looking for front-end genius

I have what I think is a cool concept for a crossword-based game, where much of the back-end already exists (I developed it for other projects) and the concept itself borrows some elements from a very successful, existing app that is not in the crossword space (so I think there is a good chance of commercial viability).

Background on me: I am a fairly experienced and successful entrepreneur, having founded three companies and had two of them succeed (one acquired, one growing nicely). I am very much a generalist but with strong technical knowledge (back-end developer) and a product development/innovation focus.

I'm looking for a very good front-end developer who is fast and can create modern-looking, high-quality web apps. Preferrable would be to pay for some initial work, and then transition to work-for-equity/cofoundership once we know we can work together.